PUBLICATION

Running the Stop Sign: Readthrough of a Premature UAG Termination Signal in the Translation of a Zebrafish (Danio rerio) Taurine Biosynthetic Enzyme

Authors
Larkin, M.E.M., Place, A.R.
ID
ZDB-PUB-170608-17
Date
2017
Source
Marine drugs   15(6): 162 (Journal)
Registered Authors
Keywords
CSAD, Danio rerio, taurine, translational readthrough, zebrafish
MeSH Terms
  • Amino Acid Sequence
  • Amino Acids/genetics
  • Animals
  • Carboxy-Lyases/genetics
  • Codon, Terminator/genetics*
  • Cysteic Acid/metabolism
  • Point Mutation/genetics
  • Protein Biosynthesis/genetics*
  • Taurine/genetics*
  • Zebrafish/genetics*
PubMed
28587202 Full text @ Mar. Drugs
Abstract
The UAG termination codon is generally recognized as the least efficient and least frequently used of the three universal stop codons. This is substantiated by numerous studies in an array of organisms. We present here evidence of a translational readthrough of a mutant nonsense UAG codon in the transcript from the cysteine sulfinic acid decarboxylase (csad) gene (ENSDARG00000026348) in zebrafish. The csad gene encodes the terminal enzyme in the taurine biosynthetic pathway. Taurine is a critical amino acid for all animals, playing several essential roles throughout the body, including modulation of the immune system. The sa9430 zebrafish strain (ZDB-ALT-130411-5055) has a point mutation leading to a premature stop codon (UAG) 20 amino acids 5' of the normal stop codon, UGA. Data from immunoblotting, enzyme activity assays, and mass spectrometry provide evidence that the mutant is making a CSAD protein identical to that of the wild-type (XP_009295318.1) in terms of size, activity, and amino acid sequence. UAG readthrough has been described in several species, but this is the first presentation of a case in fish. Also presented are the first data substantiating the ability of a fish CSAD to utilize cysteic acid, an alternative to the standard substrate cysteine sulfinic acid, to produce taurine.
Genes / Markers
Figures
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping